B1B18 means the occupant restraint controller measured low resistance on the left side curtain squib 1 circuit. Low resistance on a squib pair reads as a short, and the ORC will not arm a circuit it cannot trust. The curtain harness runs through the pillars and the headliner, which is where this one usually starts.
The left side curtain airbag is the long bag that lives above the door openings and drops down the side glass in a side impact or a roll. Its initiator connects to the ORC through two wires, (R1) left curtain squib 1 line 2 and (R3) left curtain squib 1 line 1, and the module reads the resistance across them with the ignition on.
The factory definition is LEFT SIDE CURTAIN SQUIB 1 CIRCUIT LOW, and the set condition is that the ORC detected low resistance of the left curtain squib 1 circuits. Something has given those two wires an easier path to each other than the squib itself provides.
That harness runs a long way. It leaves the module area, goes out to the A pillar, up behind the trim, and back along the roof rail toward the rear of the cabin. Anything that has been apart along that route is a candidate, and so is any water that has found its way into the headliner.
Circuit fault. The ORC measures this resistance live, so it tells you about the condition of the wiring right now rather than about a past event, and it does not lock the module. Any vehicle that actually deployed its curtain will have deployment codes stored alongside this one, and those are a separate matter.
No. Clearing the module's memory does nothing about a short between two wires. The curtain connector, the harness, or the bag has to be repaired before the airbag light goes out.
Dry and clean the curtain connectors before condemning parts, because corrosion is the most common cause on this circuit. If the curtain itself is shorted internally, we stock genuine OEM side curtain airbags, and they are specific to body style and roof configuration, so have the vehicle details ready. If the car has been in a side impact and the module is holding crash data, our airbag module reset handles that after the wiring is repaired.
B1B18 shows up on Chrysler, Dodge, Jeep, and Ram vehicles that use an ORC and have side curtain airbags, roughly 2006 through the middle of the 2010s. The 2007 Jeep Grand Cherokee, 2011 Dodge Durango, and 2013 Chrysler 200 manuals all carry the code. On later FCA platforms a left curtain problem reports as B0020 in the generic range. Vehicles ordered without side curtains do not have this circuit at all, which is worth remembering if you are dealing with a swapped module.
Pull the A pillar trim on the left side and find the curtain connector. Look for green on the pins, water staining on the trim, and a crushed or pinched section of loom. Clean and dry anything you find, reconnect, and rescan before you order a part. If the connector is clean, put a load tool on it and see whether the code drops, which separates the bag from the harness.
B1B19 is the same circuit reading high instead of low, B0020 is the generic left side deployment code, and B0028 covers the right side.
Related codes: B1B19, B0020, B0028
Keep reading:
Code scope: Chrysler, Dodge, Jeep, Ram. The same number can mean something different on another manufacturer, so match the code to your make before you act on it.
A reset clears stored crash data. A replacement part fixes a hardware fault. We have read these codes since the nineties and will tell you which one you are looking at.
Genuine OEM, tested, and shipped ground from Jacksonville, Arkansas.
Chrysler parts and codes · Do not see it listed? Request a part or call 501-988-0611.